WO2008018616A1

WO2008018616A1 - Aqueous coating composition and coated article

Info

Publication number: WO2008018616A1
Application number: PCT/JP2007/065875
Authority: WO
Inventors: Shinya Yumoto; Isao Kamimori; Takashi Kawasaki; Hideaki Katsuta
Original assignee: Kansai Paint Co., Ltd.
Priority date: 2006-08-09
Filing date: 2007-08-08
Publication date: 2008-02-14
Also published as: JPWO2008018616A1

Abstract

Disclosed is a coating composition containing a hydroxyl group-containing aqueous resin, a crosslinking agent and a plant-based filler, which coating composition is characterized in that a cured coating film thereof having a thickness of 40 μm has a soft feel value within the range of 0.8-1.5. Also disclosed are a coating film structure and a coated article. The coating composition enables to obtain a coating film having a moist soft texture and a unique tactile feeling due to the plant-based filler.

Description

Water-based paint composition and coated article

Technical field

The present invention relates to an aqueous coating composition and a coated article that can form a coating film excellent in texture and touch.

Background art

Traditionally, industrial products such as automobile interior parts and electrical product books have been painted for the purpose of protecting materials. In addition to protecting products, they are also painted in various colors to enhance the consumer's impression of the product. In recent years, in order to enhance the product power of various industrial products, it has been required to provide not only colors but also high-quality textures, in particular, textures that are different from conventional ones. As a different texture, for example, a new texture is developed by adjusting wrinkles on the surface of the coating film.

For example, car interior parts such as instrument panels may be painted with a matte finish to give a high-quality texture or feel. Also, in the fields of home appliances and interior goods, there are cases where matt paint is applied as well.

For matt paint, matt paint is usually used. A matte paint is a standard top coat paint that is further scattered with light inside the paint film by adding inorganic powders such as silica, diatomaceous earth, alumina, carbonic acid, and fine powders of acrylic resin. The effect is given. The paint film obtained by painting has a soft texture with reduced wrinkles, but the hardness of the paint film itself is the same as that of ordinary paint with wrinkles. The cold feeling when touched does not change, so it does not show a good touch.

Japanese Patent Application Publication No. 2 0 0 5— 1 3 9 2 7 3 describes a paint that can form a coating film with a good touch feeling and a soft feeling, a moist feeling and a smooth feeling. A two-part curable urethane coating composition containing a resin solution containing acrylic polyol at a specific ratio and a hardening agent solution containing polyisocyanate, and further containing urethane resin beads and an organic matting agent. It is disclosed. However, in this paint, the resin component that forms the paint film is the same as the resin for ordinary topcoat paint film, so the paint film itself is hard, and a soft touch is not obtained. It is insufficient.

Japanese Patent Application Publication No. 2 0 0 4-5 8 0 4 4 is excellent in workability and finish at the time of construction, prevents generation of cracks, and further, feel, aromaticity, absorption. As a coating method that can form a coating film with excellent coating properties such as moisture-releasing properties, a base coating containing a specific amount of a cationic water-dispersible resin solution with a pH of 7 or less, and an aggregate containing plant powder A method of coating a paint consisting of the two components is mixed and used at the time of use. However, since the disclosed paint is a two-component system, it is necessary to stir and mix immediately before painting, and there is a problem in workability. The present invention also relates to a coating method for forming a coating film excellent in physical properties such as tactile sensation, aromaticity, moisture absorption and desorption, etc. for building interior materials. In this method, the formed coating film The softness is insufficient, and the texture and feel are inadequate. Disclosure of the invention

An object of the present invention is to provide a water-based coating composition and a coated article which have a moist and soft texture and can provide a unique feel by a plant-derived filler. The present invention

[Aspect 1]

A water-based coating composition containing a hydroxyl group-containing aqueous resin, a crosslinking agent and a plant-derived filler, and a cured coating film having a thickness of 40 m obtained by coating the coating composition, A water-based coating composition characterized by having a soft field value in the range of 1.5,

[Aspect 2]

The aqueous coating composition according to aspect 1, wherein the plant-derived filler is cork powder,

[Aspect 3]

The aqueous coating composition according to aspect 1 or 2, wherein the hydroxyl group-containing aqueous resin is a hydroxyl group-containing polyurethane resin, and the crosslinking agent is a polyisocyanate compound,

[Aspect 4]

The aqueous coating composition according to any one of aspects 1 to 3, further comprising an aqueous polyurethane resin having no hydroxyl group,

[Aspect 5]

The aqueous coating composition according to any one of aspects 1 to 4, further comprising a color pigment and / or a dye, and

[Aspect 6]

A coated article obtained by coating the water-based paint composition according to any one of embodiments 1 to 5,

About.

According to the aqueous coating composition of the present invention, the aqueous coating composition was obtained by coating the aqueous coating composition so as to have a predetermined film thickness by containing a hydroxyl group-containing aqueous resin, a crosslinking agent, and a plant-derived filler. The SF value of the coating is in the range of 0.8 to 1.5, and it has a moist and soft texture. A unique tactile sensation with plant-derived filler can be obtained. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, preferred embodiments of the present invention will be described in detail. However, it should be understood that the present invention is not limited to these embodiments, and that various modifications can be made within the spirit and scope of implementation. . In the present invention, the hydroxyl group-containing aqueous resin is usually in the molecule.

Examples thereof include water-soluble or water-dispersed resins having two or more hydroxyl groups, such as acrylic resins, polyester resins, polyurethane resins, silicone resins, fluorine resins, and grafts of these resins. Among these, a polyurethane resin is particularly preferable from the viewpoint of expressing a unique tactile sensation.

The polyurethane resin is, for example, a resin obtained by reacting a polyol, a compound having an isocyanate group, and a chain extender in the presence of an emulsifier. For example, the polyurethane resin is obtained by forcibly emulsifying or self-emulsifying a prepolymer in water. Although there is a day purge, it is not limited to these.

The number average molecular weight Mn of the polyurethane resin is preferably in the range of 10:00 to 30000, more preferably in the range of 1500 to 10:00. The acid value of the polyurethane resin is preferably 10 to 8 O mgK OH / g, more preferably 15 to 40 mg KOHZg, and the hydroxyl group content is preferably 0.5 to 6% by mass, More preferably, it is in the range of 1.0 to 4% by mass.

The number average molecular weight in the present specification means a value measured by gel permeation chromatography (GPC) using a standard polystyrene calibration curve. The acid value means a value measured by the method described in JISK 5 60 1—2-1, and the hydroxyl content is JISK 0 0 7 It means a value calculated by the method described in 0.

In the present invention, the crosslinking agent is a substance having a functional group capable of reacting with the hydroxyl group of the hydroxyl group-containing resin, and examples thereof include polyisocyanate compounds and Z or amino resins.

Examples of the polyisocyanate compound include aliphatic diisocyanates such as lysine diisocyanate, hexamethylene diisocyanate, and trimethylhexane diisocyanate; cyclic aliphatic diisocyanates such as hydrogenated xylylene diisocyanate. Neato, isophorone diisocyanate, methylcyclohexane

2,4 (or 2,6) -diisocyanate, 4,4, -methylenebis (cyclohexylisocyanate) and 1,3 — (isocyananamethyl) cyclohexane; aromatic diisocyanates, for example Tolylene diisocyanate, xylylene diisocyanate and diphenylmethane diisocyanate; organic polyisocyanate, for example, trivalent or higher polyisocyanate, for example, lysine triisocyanate, organic An adduct of a polyisocyanate and a polyhydric alcohol, a low molecular weight polyester resin, water, or the like, or a cyclized polymer (for example, isocyanurate) of the above organic diisocyanate, or a piureto type adduct is mentioned. These can be used alone or in combination of two or more.

Examples of the amino resin include urea resin, melamine resin, and benzoguanamine resin, and melamine resin is particularly preferable. As the melamine resin, an alkyl etherified melamine resin etherified with an alkyl group such as methyl, ethyl, n-butyl, and isoptyl can be used. The melamine resin may have a methylol group or an imino group, and either hydrophobic or hydrophilic can be used. T JP2007 / 065875 The content of the crosslinking agent in the coating composition of the present invention is such that the equivalent ratio of the functional group of the crosslinking agent to the hydroxyl group of the hydroxyl group-containing resin is 0.5 from the viewpoint of physical properties of the coating film. It is preferably in the range of 1.0 to 3.5: 1.0.

In addition to the hydroxyl group-containing resin and the crosslinking agent, an aqueous polyurethane resin having no hydroxyl group can be added to the coating composition of the present invention for the purpose of further increasing the soft fill value described later.

The aqueous polyurethane resin having no hydroxyl group can be obtained, for example, by introducing a hydrophilic component necessary for stable dispersion in water into the main chain of the polyurethane skeleton or by dispersing with an external emulsifier. And an aqueous dispersion of polyurethane.

The amount of the aqueous polyurethane resin having no hydroxyl group in the present invention is in the range of 20 to 80 parts by mass based on 100 parts by mass of the total solid content of the vehicle-forming resin in the coating composition. And more preferably in the range of 40 to 60 parts by mass.

The plant-derived filler of the present invention means powders obtained by drying or crushing bark of various trees, stems or roots of herbs, leaves or grains. Specific examples of the above plant-derived filler include bamboo powder, wood powder, 'rice husk powder, coconut shell powder, bark powder, coffee beans, tea leaves, pulp powder, kenaf powder, paper powder, hemp powder, cotton powder, corn Examples include pulverized cores of peanuts, ground peanut shells, okara, bran meal, soybean meal, soy sauce cake, and dried bean meal. These plant-derived fillers can be used alone or in admixture of two or more. In the present invention, cork powder obtained by drying the bark of cork oak is preferable from the viewpoint of the feel of the coating film obtained by painting among the plant-derived fillers. The cork powder is a by-product generated when cork stoppers, flooring materials, heat insulating materials, etc. are produced from cork birch bark and has a low environmental impact. Have advantages.

The shape and particle size of the plant-derived filler are not particularly limited, but a particle size of 100 or less is preferable from the viewpoint of the surface state of a coating film obtained by coating. Specifically, it is possible to use a filler classified with a 100 mesh wire mesh (about 1 49 m).

The plant-derived filler can be used as it is after dried and pulverized, but it can also be used after bleaching before drying. The bleaching treatment means, for example, treatment with an aqueous sodium hypochlorite solution, an aqueous hydrogen peroxide solution, or the like. Further, the plant-derived filler can be further dyed after being bleached. For the dyeing treatment, not only synthetic dyes used industrially but also natural dyes can be used. Natural dyes include, for example, plant leaves, stems, bark, roots, flowers and fruit powders and plant dyes made from liquids or powders extracted from them, ore dyes produced by finely pulverizing ores or rocks And mud dyes produced by finely pulverizing mud and the like.

The content of the plant-derived filler is based on the resin solid content of 100 parts by mass of the hydroxyl group-containing aqueous resin composition from the viewpoint of curability after coating film formation and physical properties of the obtained coating film. It is preferably in the range of 5 to 300 parts by mass, preferably in the range of 10 to 60 parts by mass, and more preferably in the range of 15 to 40 parts by mass.

The coating composition of the present invention can further contain a colorant. Coloring pigments and / or dyes can be used as the coloring material. As the color pigment, conventionally known pigments for ink or paint can be used singly or in combination of two or more. Specific examples of the coloring pigment include, for example, metal oxide pigments such as titanium oxide and iron oxide, composite gold oxide pigments such as titanium yellow, T JP2007 / 065875 Pump rack, azo pigment, quinacridone pigment, diketopyrrolopyrrole pigment, perylene pigment, perinone pigment, benzimidazolone pigment, isoindolinone pigment, isoindolinone pigment, metal Chelate pigments, phthalocyanine pigments, indanthrone pigments, dioxane pigments and indigo pigments. In addition, a known surface treatment such as an acid treatment and / or a base treatment, a force coupling agent treatment, a plasma treatment, or an oxidation and Z or reduction treatment can be used.

In the case of using the above-mentioned color pigment, the blending amount thereof is from 100 parts by mass of the resin solid content of the hydroxyl group-containing aqueous resin composition in the coating composition from the viewpoint of coloring power and finished appearance of the obtained coating film. Based on this, it is preferably 50 parts by mass or less, particularly preferably in the range of 0.1 to 20 parts by mass.

Further, as a coloring material, a general dye for paint or ink may be used alone or in combination of two or more. Specific examples of such dyes include synthetic dyes such as azo dyes, anthraquinone dyes, copper phthalocyanine dyes and metal complex dyes, and the above-mentioned natural dyes.

When the dye is contained, the addition amount is 0 based on 100 parts by mass of the resin solid content of the hydroxyl group-containing aqueous resin composition in the coating composition from the viewpoint of the hue and transparency of the resulting coating film. It is preferably in the range of 0.1 to 10 parts by mass, particularly preferably in the range of 0.1 to 5 parts by mass. In addition, when the above-described colored pigment and dye are used in combination, the total addition amount thereof is 20 parts by mass or less based on 100 parts by mass of the resin solid content of the hydroxyl group-containing aqueous resin composition in the coating composition. I want to be there.

The water-based paint composition of the present invention includes a product produced by generation of microorganisms during paint storage. Preservatives and / or antibacterial agents can be added for the purpose of suppressing quality degradation. In addition, by adding a preservative and / or an antibacterial agent, an effect of imparting antibacterial properties to the coating film obtained by painting can be obtained. For example, 1, 2 —Benzisothiazoline-3 —one (BIT), 2 —Methyl-4 monoisothiazoline- ₃ -one (MIT), 5 —Chloro-2-methyl-1,4-isothiazoline-3 —one (CL-one MIT ), 2-Hydroxymethylamino ether and 2-Promo 2 -Nitroe 1,3 monopropanediol, silver antibacterial agent, and inorganic antibacterial agent, such as zeolite In addition, antibacterial agents derived from natural products such as persimmons can be used.

The content of the preservative and / or antibacterial agent in the coating composition of the present invention is generally based on 100 mass parts of the resin solid content of the hydroxyl group-containing aqueous resin composition in the coating composition. It is preferably in the range of 0.1 to 10 parts by weight, particularly preferably in the range of 0.1 to 5 parts by weight. Further, the coating composition of the present invention may contain various additives as desired. For example, solvents such as water and organic solvents, rheology control agents, pigment dispersants, anti-settling agents, curing catalysts, antifoaming agents, surface conditioners, antioxidants, UV absorbers, extender pigments, wrinkle conditioners Etc. can be added. The coating composition of the present invention can be prepared by mixing the above-described components and dispersing in water. Usually, at the time of coating, the solid content of the coating composition is preferably adjusted to a range of 15 to 50% by mass based on the coating composition, and is preferably 20 to 40% by mass. It is more preferable to adjust to the range.

In the case of preparing the coating composition of the present invention, for example, the plant-derived filler is previously mixed with a small amount of a resin and / or a pigment dispersant, and water. After preparing a dispersion by mixing, the dispersion can be sequentially mixed with other components to prepare a coating composition. Since the surface of the plant-derived filler can be easily wetted by pre-dispersing the plant-derived filler with resin and / or pigment dispersion and a solvent, it is preferable from the viewpoint of production cost. Furthermore, it is possible to prepare a coating composition with relatively little change in viscosity over time.

Here, an example of the preparation method of the coating composition of this invention is demonstrated. 100 parts by mass of the above plant-derived filler is mixed with 150 parts by mass of polyurethane resin as a solid content, and water is added to adjust the total solid content concentration to 40% by mass. Stirring capable of performing revolution simultaneously It can be prepared by stirring and dispersing using a defoaming apparatus. In the coating composition of the present invention, the ratio of the solid content mass of the resin to the mass of the plant-derived filler is preferably about 1.0 to about 1.5, and the solid content of the coating composition is The partial concentration is preferably adjusted to be 25 to 60% by mass.

In the coating composition of the present invention, the soft film value of the cured film having a thickness of 40 m is in the range of 0.8 to 1.5. The soft field value is a numerical value that can quantify the texture that feels soft when you touch the paint film with your fingertip. Specifically, the soft field value means a value obtained by calculation from various measured values according to the following formula.

SFV a 1 ue = 0. 1 3 [2. 3 4 (log (MIU + MM D) — 2. 7 3) + 0. 0 3 [— 0. 9 1 log (R a XMMD) 1 1. 5 5 ] + 0. 1 1 [— 6. 3 6 1 ogqmax— 3.5 5] + 0.6 8 [— 1. 1 1 1 og HU + 1. 6 1]

Where SF value is an abbreviation for soft field value, and MIU, D, Ra, qmax and HU are friction coefficient, friction coefficient average deviation, arithmetic average roughness, surface differential heat, and 2007/065875 This means biversal hardness.

The friction coefficient M I U and the friction coefficient average deviation MMD are values obtained from the surface friction resistance value measured using a friction tester KE S—SE (trade name, manufactured by Kato Tech Co., Ltd.). The surface differential heat q m a x is a value measured by a precision rapid thermal property measuring device KE S—F 7 (trade name, manufactured by Kato Tech Co., Ltd.). The arithmetic average roughness Ra is a value measured by a surface roughness meter SURFCOM 010 (trade name, manufactured by Tokyo Seimitsu Co., Ltd.). Further, the universal hardness HU is a value measured by a hardness meter FISHCHRER 100 (trade name, manufactured by Fisher Instrument Co., Ltd.).

The measurement method of the soft feel value is described in "Kasumi Yasuda et al., Quantitative evaluation of texture in paint, paint engineering V ol. 3 6, No. 2, p. 40 (2 0 0 1)". It is disclosed.

The present invention also relates to a coated product obtained by coating the substrate with the coating composition.

The substrate in the coated article of the present invention may include metallic materials such as iron, zinc, aluminum and magnesium and alloys containing these, and non-metallic materials such as glass, plastics and foams. The base material can be subjected to a degreasing treatment and / or a surface treatment, if desired.

In addition, a metal substrate obtained by plating or vapor-depositing the metal material or forming an undercoating film and / or an intermediate coating film can be used as the base material. A substrate in which an undercoat film and / or an intermediate coat film is formed on the metal or nonmetal material is particularly preferable.

The undercoat coating film is formed to conceal the surface of the material and impart anticorrosion and antifungal properties to the material. It can be obtained by painting, drying and curing the material. The type of the undercoat paint is not particularly limited, and examples thereof include an electrodeposition paint and a primer.

The intermediate coating film is formed to conceal the surface of the material and the undercoat film, and to provide adhesion, chipping resistance, and the like. It can be obtained by applying an intermediate coating, drying and curing. The type of intermediate coating is not particularly limited, and known types can be used. For example, an organic solvent-based or water-based intermediate coating containing a thermosetting resin composition and a pigment as essential components is preferably used. can do.

When using a base material on which an undercoat film and / or an intermediate coat film is formed on the above metal or non-metallic substance, the undercoat film and Z or the intermediate coat film are heated and crosslinked and cured. The coating composition can be applied later. Alternatively, the coating composition can be applied onto an uncured undercoating film and Z or intermediate coating film.

The coating composition of the present invention can be applied or dip-coated by using a coating method such as air spray, airless spray, roll roll overnight, mouth lash brush, brush or the like. The film thickness is preferably in the range of 20 to 80 m, and more preferably in the range of 30 to 80 m, as a dry film thickness. The resulting wet coating can be dried at room temperature, but when heated at about 60 ° C to 80 ° C for about 20 to 60 minutes, a coating with excellent tactile sensation is formed. Next, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to these examples. Example 1. Preparation of pigment dispersion

In the composition shown in Table 1, water-based polyurethane resin A, deionized water, and color pigment were put into a mayonnaise bottle with a volume of 4500 m 1, mixed with stirring, and then the same volume of 1.5 mm. Glass beads with a diameter were introduced, and after sealing, dispersed with a paint conditioner for 1 hour. The dispersion was filtered through a wire mesh to remove the glass beads to obtain a pigment dispersion. table 1

Aqueous polyurethane resin A Bihydrol PR340 solid content 40% by mass

(Product name, Sumika Bayer Urethane, polyurethane resin)

Titanium dioxide pigment T I TAN IX JR-903

(Product name, Tica, titanium white) Iron oxide pigment Todakara Ichi KN-0

(Product name, manufactured by Toda Kogyo Co., Ltd., ferric oxide) Yellow iron oxide pigment TAROX LL-50

(Trade name, manufactured by Titanium Industry Co., Ltd., hydrous iron oxide) Carbon black pigment RAVEN 5000ULT3-P

(Product name, COLUMB IAN CARBON, carbon black) 2. Preparation of coating composition

For Examples 1 to 3 and Comparative Examples 1 to 3, with the dispersion formulation shown in Table 2, the hydroxyl group-containing aqueous resin B, water and cork powder were formulated in a container for a defoaming stirrer, and the formulation Were simultaneously mixed and degassed. Furthermore, with the blending formulation shown in Table 2, resin, deionized water, etc. were added and mixed while stirring. For Comparative Example 4, the aqueous reaction-curing fine elastic base material for exterior use, the cork powder and water were mixed with the formulation shown in Table 2 while stirring.

Table 2

Hydroxyl-containing aqueous resin B Bihydrol XP2429 Solid content 55% by mass

(Product name, Sumika Bayer Urethane Co., Ltd., hydroxyl group-containing polyurethane resin)

Clear paint click 2026GL clear 31% by mass

(Product name, Kansai Paint, nitrocellulose-modified acrylic resin-based clear paint)

CLEAR ONE BASE Evening PG60 BASE 44% solids

(Product name, Kansai Paint, hydroxyl-containing acrylic resin) Dilution thinner Click No. 1000 thinner

(Product name, Kansai Paint, mixed solvent)

Cork powder Commercial product refined to a particle size of 200 mesh or less Urethane beads Art Pearl P-800

(Product name, manufactured by Negami Kogyo Co., Ltd., urethane beads)

Pigment dispersion prepared in Pigment dispersion 1

Aqueous polyurethane resin A Bihydrol PR340 Solid content 40% by mass

(Product name, polyurethane resin, manufactured by Sumika Bayer Ureng Co., Ltd.) Crosslinking agent A Baihijoule 3100

(Product name, Sumika Bayer Ure Yun company,

Hydrophilic hexamethylene diisocyanate)

Cross-linking agent B Soflex 5000 curing agent, solid content 75% by mass

(Product name, Kansai Paint, Hexamethylene Di

Isocyanate-based curing agent)

Base adjustment material Ares holder G2

(Trade name, manufactured by Kansai Paint Co., Ltd., water-based reaction-curing fine elastic base material for exterior use). 3. Preparation of test plate.

For each of Examples 1 to 3 and Comparative Examples 1 to 4, two test plates were prepared as follows.

For Examples 1 to 3 and Comparative Examples 1 to 3, an ABS resin panel obtained by degreasing the coating composition prepared in 2. above using a solvent in advance

(1500 mm x 50 mm) was coated with a spray gun so that the film thickness was 40 m. After painting, it was left at room temperature for 10 minutes, and then heated in a warm air drying oven at 80 ° C. for 30 minutes to cure the coating film to prepare a test plate. For Comparative Example 4, the above A B S resin panel

(15 mm x 50 mm) was applied with a doctor blade (6 m i 1) and dried at room temperature.

4. Evaluation test

1) Soft field value (SF value): In order to evaluate the texture of the test plate created in 3. above, the soft field value of the test plate was measured according to the above formula. The results are shown in Table 3.

2) Moist feeling: In order to evaluate the touch feeling of the test plate prepared in 3, the moist feeling when touched with a finger was evaluated according to the following criteria. Table 3 shows the results.

〇: Resilient when touched by hand.

Δ: Slightly elastic when touched by hand.

X: Almost no elasticity when touched by hand.

3) Adhesiveness: Using a cutlet, cross cuts were made in a 2 mm x 2 mm size grid pattern on the surface of the coating film to make a total of 100 grids. After that, cellophane tape ^TM is attached to the surface of the coating film, and the tape is peeled off by pulling it in a direction of 45 degrees with respect to the coating film surface. Evaluation was made according to the criteria. The results are shown in Table 3. O: 100 of the 100 grids remain.

Δ: 9 9 to 95 of the 100 0 grids remain.

X: Of the 100 grids, only 94 or less remain. 4) Water resistance: Each of the test plates prepared in 3 was immersed in 40 warm water for 10 days, pulled up, left in a laboratory at 20 ° C for 1 hour, and then The same adhesion test as in 3) was performed, and the state of the grid was evaluated according to the following criteria. The results are shown in Table 3.

〇: Out of 100 0 grids, 100 0 remain.

Δ: 9 9 to 95 of the 100 0 grids remain.

X: Of the 100 grids, only 94 or less remain. Table 3

Industrial applicability

INDUSTRIAL APPLICABILITY Since the present invention can provide a coating composition applicable to various industrial products, particularly interior parts of automobile bodies and home appliances, it is industrially useful.

Claims

The scope of the claims

1. A water-based coating composition containing a hydroxyl group-containing aqueous resin, a crosslinking agent, and a plant-derived filler, and a cured coating film having a thickness of 40 m obtained by coating the coating composition is 0. A water-based coating composition having a soft field value in the range of 8 to 1.5.

2. The aqueous paint composition according to claim 1, wherein the plant-derived filler is cork powder.

3. The aqueous coating composition according to claim 1 or 2, wherein the hydroxyl group-containing aqueous resin is a hydroxyl group-containing polyurethane resin, and the crosslinking agent is a polyisocyanate compound.

4. The aqueous coating composition according to any one of claims 1 to 3, further comprising an aqueous polyurethane resin having no hydroxyl group.

5. The water-based paint composition according to any one of claims 1 to 4, further comprising a color pigment and / or a dye.

6. A coated article obtained by applying the water-based coating composition according to any one of claims 1 to 5.